Finding the Fourth Proportional to 8,320.56, 12,495.71 and 7,986.10

Step by Step Solution

1. Step 1: Write the proportion equation
   8,320.56 : 12,495.71 = 7,986.10 : x
2. Step 2: Convert to fraction form
   8,320.56/12,495.71 = 7,986.10/x
3. Step 3: Cross multiply
   8,320.56x = 12,495.71 × 7,986.10
4. Step 4: Simplify right side
   8,320.56x = 99,791,949.70
5. Step 5: Solve for x
   x = 99,791,949.70/8,320.56
6. Step 6: Final answer
   x = 11,993.42